If you run a blog changes are you've messed with it's code. Maybe to add a picture or move some piece of code around to change the layout. I've been blogging since 2003 and all of that has been using HTML. It's easy to understand and simple to figure out. I've recently switched over to Blogger's new design which uses XML and I'm not a big fan of it. It's much more difficult to figure out than basic HTML. I spent almost two hours yesterday messing with it just to move a few things around. I eventually got what I wanted, sort of. It's not exactly what I would like but it'll do. I don't think I'm going to be mastering it anytime soon.